During the writing process in disc drivers there occurs the problem of non-linear transition shift (NLTS). This causes the actual pulse edge transition which switches the magnetic domain of the magnetic media to shift early by as much as 30%. The extent of the shift varies with the media and/or components such as the write coil. Thus each manufacturer must tune the equipment to optimize the reduction of the shift. In one conventional approach an open loop delay line with a number of taps in 2% increments is used to provide the manufacturer with a selection to choose the necessary delay for his particular configuration of media and components. This open loop approach does not provide feedback to adjust for changes in the environment that can offset the shift.